Expansive reamer



y 1929. s. CAMPBELL ET AL EXPANS IVE REAMER Original Filed Feb. 1, 1928 Dill rl ell Stewartl. Cam JaI72S.-7. 50% z Patented Julyj16, 1929.

UNITED STATES 1,720,998 PATENT OFFICE.

arrwan'r I. cmzann'n, or mm AND minis .1. sari-moo, or me memes,

emomua, assxenoasl'ro Joint cam, or Los arena-as, caLn'onxu.

' SIVE RELIED.

Original application med-m 1, 1918. Serial no. 250,903. Divide! and February 1-1, 1988.v

' This invention has'to do with expansive cutting tools,'reamers or underreamers. The particular design shown and explained'herein is adapted specifically to notary underreaming; but it will be'recognized'from what follows that, although the invention is 'par-. ticularly useful as airotary tool, it is not" necessarily restricted to' such specific use.

In reamers where s ring or similar actua- I tion is used for expan ing or protracting the cutters, it has been-universally the case, so far as our knowledge goes, thatthe springaction, tending at all times to press-the cutters, outwardl has caused them to ride the casing 'whlle the tool is beinglowered or pulled up through the casing. The drag of the cutters on the casing is, in many in stances, quite 'forcible, particularly as the tool is being lowered; because the cutters are usually expanded by some kind of wedging action, actuated by. the spring, and the upward drag of the casing onv the cutter accen-. tuates the wedging action. Thecutt'ers thus, 'inmany instances, press outwardly with con-, siderable force against the casing, cutt ngand scoring the :casing, and causing consider-' able wear on the cutters.

It is the major object of this invention to provide a cutter locking I or cutter holding means which will hold the.cutters'1 nward1y in their collapsed positions; and to provide such a cutterrholding or locking means, in a springactuated expanding reamer, in such a' manner that althoughthe spring is avail.-

' able for the performance of its usualcutter' expanding function, the expanding actionof the 2 ring onthe cutters is temporarily an underreamer having a spring actuatedexpansion with wedgin'g action, the'expandmg action of the spring is prevented when-the cutters are contracted, so that there, is then no acting force tending topress the cutters out; and thespring' pressure is, on the con trary, used for holdi-n the cutters in their retracted or collap positions. In. this present application we lllustrate a mecha-' .nis m wherein' the'cutters are caused to expend by relative long1tudinal'movemen t-- relative longitudinal movement 'as-between tion th e'specific design invo ves the longituthe cutters or cutter carriers and .the expand- 'ing mandrel. :And in this resent app1ic'a when so desired. Thus, in accordance, with our invention as applied speclfically to this application fled SeriallfoL258g541.

-the present embodiment, reference is had-to .the accompanying-drawings, in which- Fig; 1 is a central longitudinal section showing the reamer in its contracted condition- .2 is a similar view showing the reamer in its expanded condition ;V

Fig. is a cross-section on line 3--3 of Fig. 2; i

4 is a cross-section on line 4-4 of 1g. 4 Fig. 5 is a cross-section online 5-5 of Flg. 2; F ig. 6 is a cross-section on line '66 of 1g. Fig. 7 is a detail section on line 77 of Fig. 1. v

' n the drawings a suitable tubular body is shown at 10, havi'n'g'at its lower end thestationary with respect to the body, is centrallymounted in any suitable manner, For instance, it is shown as having a shouldered enlargementl if overwhich a screw threade'd sleeve 15 is fitted,- the sleeve screwing onto the body at 16. And the upper end' of the mandrel has a taper-threaded pin 17 for connectlonwith the usual drill stem, or, with a sub 18 which connects with the drill stem. Y

The mandrel, so mounted,-i's longitudinally immovable with reference to the body,.but it rotatable-therein.

In thespecifie design here shown, the mandrel has a comparatively large upper part 14" which is cylindric and fits the cylindric bore 10' of the body so that the mandrel is given a good rotary bearing of some longitudinal extent, in the body., The lower part.

of thislarge mandrel portion 14 is provided with. three shallow recesses or slots 14?, which reachup from the level of the horizontal shoulders 14 located atthe lower-end of the large mandrel portion 14 intermediate the slots 14. three in number, but merely because, we choose here to show a reamer having three cutter carriers. Below shoulders 14' the mandrel is'reduced in size as shown at 14; and a conical part 14' leads between the reduced part 14 and the slot bottoms at the level of-shoulders 14", the upper end of the conical part being of the same diameter as the bottoms of slots 14. Fig. 2 shows this relationship.

expansion of the cuttersmay"be of any desired or preferred design. instance there is shown simply a mandrel having the tapered part 1 4' and a tapered portion 14 at its lower'end. Cutter carriers 20fit slidably in slot 21 through the body walland have lateral wings 22 which bear outwardly. against the inner wall sur-- face to limit outward movement of the out ter carriers. Q The rear surfaces of the carriers are so formed that, byinter-action with the mandrel, they are forced outwardly to the expanded position shown in Figs. 2 and 3, when they move upwardly in slots 21; and may move inwardly to the collapsed position .shown in Figs. 1 and 4, when they are moved downwardly in the slots. This interaction of the carriers and mandrel will be well understoodfrom a consideration of the drawin and needs no further explanation here, t is only of present interest that relative longitudinal motion between the man- I,

drel and carriers causes expansion and con-.

traction of the cutter carriers. The specific interformatlon of the carriers and m'andrel, as here shown, is, in fact, not our spe-' eific invention, but the, invention of John Grant, as set -out in his application Serial No. 254,266, filed February 14, 1928; our

invention is in the application of our cutterlocking means to 'anycutter or cutter carrier that expandsand contracts by relative longitudinal movement. I I

Below the cutter carriers is a cutter propeller 25,- shown in the form of a cylindric pring 27 also surrounds the pipe provides communication for cir-' -culating the water between-the longitudinal circulat1on'passage30 in'mandrel 14 and the circulation passage 31 of the drill bit. And at the same time the wash pipe feeds .the

We mention the slots as being 'In the present rin%27 housed in the ower part y pipe 26. The

circulating water to the lower body bore 32 in which sprin 27 is housed. The lower end.

end of the wash pipe. Or perforations such as indicated at 33 may be provided. To

cause circulation of a certain amount of" wash water throu h the spring chamber and also to points un er the cutters, discharge pamages 34 are provided under the cutters,

.. ,the innerends of these discharge passages The mandrel formation below the part 14'-in fact, the whole formation of the 'mandrel' in so far as it functions to cause shownin igsa 1 and 4, theupper square being uncovered by the upward movement of shouldered end 35 ofeach cutter carrierbecutters they rest back against '/'the' smaller part 'of the mandrel; and, although they could be moved outwardly'b 'a suflicient outward force, there are no suc outward forces brought to play-upon the cutters or'cutter carriers in this contracted condition; or at least .no outward forcesof suflicient magni tude to move the cutters outwardly from their clamped positions, For, in the position of Fig. 1, it will. be seen that the cutters are, in effect, clamped by the action of spring 27 between the cutter propeller 25 and the mandrel shoulders 14"; and this, clamping action is quite strong because of the strength of spring 27 After the tool has been lowered through i the casing, then the mandrel is rotated with reference to the body and cutters, the-drag of the drill hoie svall on the cutters or cutter being suficient tohold the body from. rotation while the mandrel is rotated withi-nfit.

-By rotation through approximately one- .sixth of a revolution, the mandrel 14 are brought into register with the upper ends of the cutter carriers, and the spring immediately the osition of ig. 2, then per inner parts of t 0 carriers entering t mandrel re-,

cesses. In their upper movements the carriers aremoved outwardly, due tothe action of the conical mandrel part at .14 upon which the diagonal carrier'surface 20' rides, (1 due also to the conical mandrel part at 14' upon which the carrier face 20" rides;

so that the carriers their upper'exanded positions asishown in-Fig's. 2 and 3.

n this position the upper inner arts of the carriers fitsnugly intothe man rel recesses ves the cutter carriers up to t, throwin When it is desired to remove the manner from the well it is only necessary to draw it upwardly, whenthe upper projecting ends of the carriers will come into contact with the lower end of the well casin or shoe, the carriers being relatively move downwardly toward the position of Fig. 1. At the same time the carriers are passed inwardly by reason of engagement of the well casing or shoe with the diagonal faces 40; and they are thus moved down to near the relative elevation shown in Fi 1, and are then moved inwardly to the relative contracted position shown in Fig. 1.

In this, contracted position of the cutters the tool may be removed upwardly through the casing, even though the spring 27 is, at all times tending to 'ex and the cutters against the well casing. ut this expansive action against the well casing can be .obviated by merely rotating the mandrel again to the relative position shown in Figs. -1 and the shoulders 14 over the up. per ends 0 the cutter carriers. The cutter carriers are then looked in their contracted nositions'just as they were when the tool was being lowered through the casing.

Locking the cutters against expansion for the purpose of removing them through the casing is not of so great importance as it is upon lowering the tool through the casing, because when the tool is -ing raised the drag of the casing on the cutters tends at all times-to force them down on the mandrel and force them. further inwardly. But the tool is so constructed that the cutters can be locked in either situation. 1 And, to provide for surety of locking action when the tool is drawn up in the casing, each shoulder surface it may be given a slight di-' agonal corner out it so that, even though engagement with the casing may not force the cutter carriers clear down to the posi;

tion of Fig. 1', rotation of the mandrelin a right-handed direction and the action of diagonal surfaces it on the upper ends of the carriers will force them through the slight remaining distance down totheposition of Fig. 1, so that the square shoulders 14 may pass over them to loci: them. Likewise. and

in the same 7, the upmr end of the.

carrier may have a diagonal corner surface 20. llt is only necessary to out thus diagonally one corner of each square shoulder surface 14:, or of each carrier 20, as the mandrel can always be rotated in a right-handed direction; there being no necessity of ever rotating the mandrel left-handedly.

The cutter carriers 20 may be equipped with any suitable cutting elements or edges, and it is only for purposes of illustration we have shown the carriers equipped'with' roller cutters 45. The cutting elements may be of any nature desired; for cutting or reaming in any kind of formation. Furthermore, the cutters may be of a nature to perforate or cut a well casing or pipe; the tool being particularly applicable for that purpose for the reasonthat it is expanded by relative, ro- 1 tation of the mandrel within the cutters and contracted by relative. longitudinal (upward) movement of the mandrel within the cutters, The invention is thus not limited to expansive reamers but is applicable in general to expansive tools.

' We claim:

1. In an expansive tool of the character described, a body and a cutter carrier mov-- able laterally therein for expansion and contraction, a mandrel movable longitudinally and also rotativelywith reference to the carrier, the mandrel and carrier being formed to cause lateral expansive movement of the carrier by virtue of relative longitudinal movement in one direction, and the mandrelhaving a carrier receiving recess and an adjacent carrier engageable shoulder adapted selectively to be registered with the carrier by relative rotation of the mandrel.

2. In an expansive tool of the character described, a body and a cutter carrier movable laterally therein for. expansion and contraction, a mandrel movable longitudinally and also rotatively with reference to the carrier, the mandrel and carrier being formed to cause lateral expansive movementof the ear rier by virtue of relative longitudinal movement in one direction, and the mandrel having a'plurality of circumferentially spacedcarrier receiving recesses and interspaced carrier .engageable shoulders adapted selecceiving recesses, into which the carrier eu-' tors bysaid relative; longitudinal movement, and a plurality. of aintcrspaoed carrier on- 'gageable shoulders.

lill

4. In an expansive tool of the character described, a substantially tubular body with a slotted wall, a cutter carrier movable longitudinally and radially in the wall slot, yielding means tending to move said carrier longitudinally in one direction, a rotatable mandrel within the body, said mandrel having a wedge formation adapted to cause outward radial movement of the carrier upon its longitudinal movement in said direction, and a carrier engageable shoulder on .the mandrel having a limited circumferential extent so that rotation of the mandrel may throw said shoulder into and out of registration with the longitudinal movement of the carrier.

5. In an expansive tool of the character described, a substantially tubular body with a slotted wall, a cutter carrier movable longitudinally and radially in the wall slot, yielding means tending to move said carrier longitudinally in one direction, a rotatable mandrel within the body, said mandrel having a wedge formation adapted to cause out-- ward radial movement of the carrier upon its longitudinal movement in said direction, said mandrel having a plurality of circumferentially spaced and circumferentially extending shoulders adapted to prevent said longitudinal movement of the carrier.

6. In an expansive tool of the character described, a substantially tubular body with a slotted wall, acutter carrier movable longitudinally and radially in the wall slot, yielding means tending to move said carrier longitudinally in one direction, a rotatable mandrel within the body, said mandrel having a wedge formation adapted to cause outward radial movement of the carrier upon its longitudinal movement in said direction, said mandrel havinga plurality of circumferentially spaced and circumferentially extending shoulders adapted to prevent said longitudinal movement of the carrier, and having interspaced longitudinally extending recesses into which the carrier may enter between adjacent shoulders.

7. In an expansive 'tool of the character described, a body'and a cutter carrier mov able laterally therein for expansion and contraction, a mandrel movable longitudinally and rotatively with reference to the carrier, the mandrel and carrier .being formed to cause lateral expansive movement of the car-' rier by virtue of relative longitudinal movement in one direction, and the mandrel having a circumferentially extending shoulder of limitcd extent and adapted, by relativerotative movement of the mandrel, to be thrown into and out of registration with the carrier.

8. In an expansive tool of the character described, a body and a cutter carrier movable laterally thereinfor expansion and contraction, a mandrel movable longitudinally and rotatively with reference to the carrier, the mandrel and carrier being formed to cause lateral expansive movement of the carrier by virtue of relative longitudinal movement in one direction, and the mandrel having a plurality of circumferentially spaced and c-ircuinfercntially extending shoulders adapted to be thrown into and out of the longitudinal line of movement of the carrier by relative rotating movement of the mandrel.

9. In an expansive tool of the character described, a body and a cutter carrier movable laterally therein for expansion and contraction, a mandrel movable longitudinally and rotat-ively with reference to the carrier, the mandrel and carrier being formed to cause lateral expansive movement of the carrier by virtue of relative longitudinal movement in one direction, and the mandrel having circumferentially spaced carrier stopping and carrier receiving parts adapted selectivel to be registered with the carrier by relative rotative movement of the mandrel.

In witness that we claim the foregoing we have hereunto subscribed our names this fifth day ofFebruary, 1928.

STEWART L. CAMPBELL. JAMES J. SANTIAGO. 

